Day 4: Part 1

day3/main.py

@@ -0,0 +1,30 @@
+batteries = []
+
+with open("day3/input.txt") as file:
+    for line in file:
+        batteries.append([int(c) for c in line.strip()])
+
+
+def max_12_digit_number(digits):
+    target_len = 12
+    to_remove = len(digits) - target_len
+    stack = []
+
+    for d in digits:
+        while stack and to_remove > 0 and stack[-1] < d:
+            stack.pop()
+            to_remove -= 1
+        stack.append(d)
+
+    # Falls noch nicht genug entfernt wurde (am Ende nur große Zahlen)
+    return stack[:target_len]
+
+
+total = 0
+
+for bank in batteries:
+    best_digits = max_12_digit_number(bank)
+    joltage = int("".join(map(str, best_digits)))
+    total += joltage
+
+print(total)